Bacterial barrier for indwelling catheters and other medical devices

Abstract

A novel bacterial barrier for medical devices is disclosed comprising a strip or band of oligodynamic metal connected to another conductor generally connected in open circuit to a power cell and producing a strategic circumferential zone of bacterial inhibition when the medical device is installed.

I claim: 
     
       1. A bacterial barrier for medical devices comprising: a thin, flexible nonconductive substrate;   an electric power cell;   a continuous strip of an oligodynamic metal on the substrate;   a conductive material on the substrate separated from the oligodynamic metal;   the oligodynamic metal and conductive material being connected to oxidizing and reducing poles respectively of the electric power cell such that an open circuit is formed which circuit is closed by body fluids when the medical device with bacterial barrier is installed in a patient and such that the oligodynamic metal is oxidized forming ions of the oligodynamic metal.   
     
     
       2. The bacterial barrier according to claim 1 wherein said conductive material on the substrate is a continuous strip of conductive material substantially parallel to the strip of oligodynamic metal. 
     
     
       3. The bacterial barrier according to claim 1 wherein said oligodynamic metal is selected from silver, copper, aluminum or zinc. 
     
     
       4. The bacterial barrier according to claim 1 wherein said power cell is an electrochemical cell or solar cell. 
     
     
       5. The bacterial barrier according to claim 1 wherein said conductive material is a metal more noble than the oligodynamic metal or of substantially similar ionization potential. 
     
     
       6. The bacterial barrier according to claim 1 wherein the medical device is a catheter, the substrate is an outside wall of the catheter, and the bacterial barrier is positioned around the outside circumference of said catheter such that a continuous band of the oligodynamic metal is formed. 
     
     
       7. The bacterial barrier according to claim 6 wherein the bacterial barrier is positioned on the catheter to be just within the urethral orifice when the catheter is installed. 
     
     
       8. An improved medical device for shunting body fluids having a bacterial barrier around the outside circumference thereof comprising: a nonconductive substrate;   at least one band of an oligodynamic metal on the substrate;   an electric power cell;   a conductive material on the substrate separated from the oligodynamic metal;   the oligodynamic metal and conductive material being connected to oxidizing and reducing poles respectively of the electric power cell such that an open circuit is formed which circuit is closed by body fluids when the medical device with bacterial barrier is installed in a patient and such that the oligodynamic metal band is oxidized forming ions of the oligodynamic metal.   
     
     
       9. The device according to claim 8 wherein said conductive material is on the substrate and is a band substantially parallel to the band of oligodynamic metal. 
     
     
       10. The device according to claim 8 wherein the medical device is selected from the group consisting of a catheter, an intraveneous needle, and a vascular shunt. 
     
     
       11. The device according to claim 8 wherein said conductive material is a metal more noble than the oligodynamic metal or of substantially similar ionization potential. 
     
     
       12. The device according to claim 8 wherein said oligodynamic metal is selected from the group consisting of silver, copper, aluminum, and zinc. 
     
     
       13. The device according to claim 8 wherein said power cell is an electrochemical cell or solar cell. 
     
     
       14. The device according to claim 8 comprising in addition on electrolytic gel connecting the oligodynamic metal and the conductive metal. 
     
     
       15. The device according to claim 14 wherein said oligodynamic metal is selected from the group consisting of silver, copper, aluminum or zinc.